To the point of the topcase lighting additions:
I installed a very expensive Admore kit into the Missus' NC700XD's Givi-built Honda topcase. It did not overwhelm.
Along the way I started experimenting with inexpensive LED strips and kits from Ebay and Amazon. These worked much better in terms of lighting.
The Admore processor is very good and does the best overall presentation, integrating turn signals into the topcase elements. Still, my own parts were much brighter, much less expensive, and have not failed yet.
For some reason, we have more Givi topcases than motorcycles these days. All have had LED installations. Using them in dense urban and suburban traffic has convinced me that high-mounted tail and brake lights are a significant benefit.
For the connection between the bike and case, I've standardized on a common three-pole automotive connector I got from Amazon. They have been reasonably reliable. By now, at least five of our bikes have had this personal standard connection. I haven't bothered with adding turn signals to the topcase systems, though. A bit of extra work and not much additional help- most of our bikes have been Kawasakis, which have excellent turn signals stock that are way more visible than the FJR's.
I made up little high/low intensity "processors" from some diodes and resistors and swaddled them in shrink tube. Therefore, I get tail lights and then brakes lights upon application by the "processor" taking juice from either the stock tail or brake conductors., wyed together.
I also have added cheap Chinese LED brake light strips to the rear faces of the Givi topcase mounting plates, wired high-intensity/brake light only. In the nasty traffic hereabouts, I'm almost reluctant now to go out without all of this rear lighting.
A couple of the bikes have also had ElectricalConnection.com turn signal+running light conversions, where you get a red taillight added to your OEM turn signal that syncs with the turn signal and goes out when the amber comes on. Had this on my old ZX1100 for many, many years. Adding a few lumens always seems to help.
2020 Ninja 400 in the hands of the Missus
2004 Suzuki SV650S, also Hers
In the avatar: 1966 Velocette Venom Thruxton and 1967 BSA Royal Star.